NO347062B1

NO347062B1 - A sealing device, a downhole tool comprising a sealing device and petroleum well toolstring valve comprising a sealing device

Info

Publication number: NO347062B1
Application number: NO20211067A
Authority: NO
Inventors: Harald Herabakka Glinda
Original assignee: Archer Oiltools As
Priority date: 2021-09-06
Filing date: 2021-09-06
Publication date: 2023-05-02
Also published as: NO20211067A1

Description

Introduction

The present invention is related to a sealing device for a down-hole tool, a downhole tool and a petroleum well toolstring valve comprising a drill pipe string -conveyed J-slot running tool for a top stinger on a retrievable bridge plug, both having a central connector and stinger bores, respectively.

Background and problems related thereto

One of the main purposes of having fluid communication through a removable prior art bridge plug with a stinger and a prior art J-slot sleeve running tool, and further through the bore of a drill pipe string, is to enable ventilating and balancing out gas and fluid pressure from below the plug in order to enable releasing the slips and packer of the plug without any pressure or gas gradient across the plug, and thus to prevent accelerations of the plug or uncontrolled gas release.

Therefore, in the prior art, the applicant so far has relied on using a ball valve for closing and opening the main bore through the plug mandrel. That valve is closed after setting the slips and packer seal of the plug in a casing, then testing for sealing integrity, and before disconnecting the prior art J-slot tool. When reconnecting after some elapsed time, such as hours, weeks or several months, gas may have accumulated below the packer or in the main bore of the plug, and the ball valve is opened to test the pressure below the packer, before releasing the packer and the slips. The prior art plug may have a radial valve in the mandrel below the packer so as for balancing the pressure across the mandrel, too.

Usually the central bore of the drill pipe string, the prior art central connector bore, and the prior art central stinger bore are in direct fluid communication in order for controlling the below prior art plug with fluid communication such as pressure and flow rate, directly from the drilling rig at the surface. Also, usually, in order to open or close between the prior art central connector bore and the central stinger bore there is arranged a ball valve, which is a rather delicate, multi-component tool part which is costly, vulnerable, and which requires much maintenance between runs. Further, the prior art ball valve may be subject to a pressure gradient which generates high friction, particularly when trying to start turning the ball valve element from closed to open position. The large seal diameter of the prior art ball valve seals (above and below the ball) requires a large mechanical moment to rotate the ball if the ball is under pressure from below or above, so the opening mechanism may be severely strained.

A further problem is related to sealing of ports in parts of a downhole tool where a large pressure gradient is present. In such instances, the seals can quickly become damaged and must be replaced. Such operations are time consuming and costly, and obtaining a technical solution where the seals are not damaged, or at least the seals are much less prone to be damaged, would therefore be desirable.

Other solutions found in the prior art are described in US 2018/291708 A1, US 2017/030168 A1 and US 5697449 A.

US 2018/0291708 A1 discloses a valve for use in a wellbore which includes a housing with a housing port, a slidable closure member disposed in a bore of the housing and including a closure member port, a seal disposed in the housing, and a detent disposed radially between the closure member and the housing. The closure member includes a first position in the housing where fluid communication is provided between the closure member port and the housing port, and a second position axially spaced from the first position where fluid communication between the closure member port and the housing port is restricted. In response to actuating the closure member from the first position to the second position, the closure member is configured to elastically deform the detent.

US 5697449 A describes a retrievable packoff assembly for temporarily sealing a well pipe and anchoring equipment at a subsurface location within the pipe.

Brief summary of the invention

The invention solves at least some or all of the above mentioned problems, and is defined in the independent attached claim.

Hence, there is provided a sealing device for a down-hole tool comprising an inner cylindrical body and an outer cylindrical body which are provided with respective axial bores and are coaxially arranged, and where the inner cylindrical body is provided with a port extending in a radial direction of the inner cylindrical body, in which port the sealing device is adapted to be arranged movably in said radial direction, the sealing device having a longitudinal axis which extends in the same direction as the radial direction of said port when the sealing device is arranged in the port, the sealing device comprising:

- an inner piston which is adapted to be arranged in said port movable relative to the inner cylindrical body of the down-hole tool, the inner piston comprising:

a seat portion which is adapted to abut a seat in said port of the cylindrical body of the down-hole tool,

a neck portion extending outwards from the seat portion in said longitudinal direction,

an inner piston fluid conduit extending through the seat portion and the neck portion in said longitudinal direction,

- an outer piston which is adapted to be arranged in said port movable relative to the inner cylindrical body of the down-hole tool, the outer piston being movable relative to the inner piston in said longitudinal direction and guided by the neck portion of the inner piston, the outer piston comprising:

an outer piston fluid conduit extending through the outer piston in said longitudinal direction,

an outer surface which faces radially outwards when the sealing device is arranged in said port and extends circumferentially around the outer piston fluid conduit, the outer surface being adapted to form a seal against the outer cylindrical body when the sealing device is arranged in said port,

- a spring device which is arranged between the inner piston and the outer piston so that forces are exerted in opposite longitudinal directions on the inner piston and the outer piston respectively, the spring device exerting a force radially inwards on the inner piston and a force radially outwards on the outer piston when the sealing device is arranged in said port, - a first sealing element extending circumferentially around the inner piston and being adapted to seal against said port when the sealing device is arranged in the port such that radial fluid flow past the inner piston between the inner piston and the port of the inner cylindrical body is prevented,

- a second sealing element arranged between the inner piston and the outer piston preventing radial fluid flow past the neck portion of the inner piston between the outer piston and the neck portion,

- a third sealing element which is arranged in the outer surface of the outer piston and extending circumferentially around the outer fluid conduit, the third sealing element being adapted to form a further seal against the outer cylindrical body when the sealing device is arranged in said port.

The port of the cylindrical body preferably has a radially extending axis which is coaxial with the longitudinal axis of the sealing device.

The first sealing element preferably extends circumferentially around the neck portion of the inner piston.

The third sealing element preferably divides the outer surface into an inner surface part and an outer surface part.

The outer piston is preferably made of a metallic material. Two separate metallic sealing surfaces are thereby abutting against the outer cylindrical body. Such metalto-metal seals are commonly used in downhole tools, and a person skilled in the art will readily be able to choose an appropriate metallic material for the outer piston.

An outer side face of the outer piston facing the port when the sealing device is arranged in the port, is preferably provided with a plurality of canals extending along the entire outer side face or at least substantially the entire outer side face such that fluid can flow from a space between the inner cylindrical body and outer cylindrical body and into the spring recess.

The inner piston is preferably provided with a spring recess which faces the outer piston, where the spring device is arranged in the spring recess.

The spring recess is preferably provided in the seat portion of the inner piston.

The spring recess may be formed by a protruding element which extends radially outwards from the seat portion and circumferentially around the neck portion such that a spring recess is formed in which the spring device can be arranged.

The spring device is preferably a wave spring.

The inner piston fluid conduit and the outer piston fluid conduit preferably form a fluid conduit which allows a fluid to flow through the sealing device in the longitudinal direction of the sealing device.

The first sealing element, the second sealing element and the third sealing element are preferably made of an elastomer. Such elastomers are commonly used in downhole tools, and a person skilled in the art will readily be able to choose an appropriate type of elastomer for the seals.

The sealing device may be adapted to be arranged in a top stinger comprising an inner cylindrical body with a port and an outer cylindrical body with a port, the inner cylindrical body and the outer cylindrical body being coaxial and rotatable relative to each other, the sealing device being adapted to be arranged in the port, movably in the radial direction in the port.

There is further provided a downhole tool comprising an inner cylindrical body and an outer cylindrical body which are provided with respective axial bores and are coaxially arranged, and where the inner cylindrical body is provided with a port extending in a radial direction of the inner cylindrical body, wherein a sealing device as described above is arranged in the port, movably in the radial direction.

The port of the inner cylindrical body preferably comprises a seat against which the sealing device is abutting.

Preferably, the inner surface part of the outer surface and an outer surface part of the outer surface both forms a seal against fluid flow across the outer surface.

There is further provided a petroleum well toolstring valve comprising a drill pipe string conveyed J-slot running tool for a top stinger on a retrievable bridge plug, both having a central connector and central connector and stinger bores,

said J-slot running tool having

- a J-slot sleeve with J-slots for disconnectably receiving said stinger with lugs of said top stinger;

- said top stinger having

- a cylindrical stinger portion with

- J-slot connecting lugs, and

- an internal plug is arranged between said connector and central connector and stinger bores;

- a cylindrical neck is formed on said stinger portion, spanning said internal plug in the axial direction, with

- an upper stinger port into said central connector bore, and

- a lower stinger port into said central stinger bore,

so as for said cylindrical neck, when covered by said J-slot sleeve, forms an annular flow space, fluid connecting said upper and lower stinger ports and thus said central bores,

- said stinger portion having

- a rotatable outer cylindrical body arranged on an inner cylindrical body, i.e. a cylindrical inner, static, stinger valve stem body of said stinger portion, and extending and covering at least to above said lower stinger port,

- said outer cylindrical body having a sleeve valve port arranged for being aligned with said lower stinger port when rotated into an open position, wherein a sealing device as described above is arranged in the lower stinger port, movably in a radial direction of the lower stinger port.

Preferably, said stinger portion has said outer cylindrical body connected to said lugs for being rotated RH or LH by said drill pipe string for opening or closing said valve.

Preferably, said outer cylindrical body and said inner cylindrical body having rotation delimiter shoulders, respectively, arranged for limiting mutual LH or RH rotation relative to said stinger portion.

Preferably, at least one sealing o-ring arranged on said stinger portion between said lugs and said cylindrical neck.

The lower stinger port preferably comprises a seat against which the sealing device is abutting.

As mentioned above, the invention may take the form of a petroleum well toolstring valve comprising a drill pipe string -conveyed J-slot running tool for a top stinger on a retrievable bridge plug, both having a central connector and stinger bores.

The J-slot running tool may have a J-slot sleeve with J-slots for disconnectably receiving said stinger with lugs of said top stinger.

The top stinger may have a cylindrical stinger portion with J-slot connecting lugs, and wherein an internal plug is arranged between said connector and stinger bores.

A cylindrical neck may be formed on said stinger portion, spanning said internal plug in the axial direction, with an upper radial port into said central connector bore, and a lower stinger port into said central stinger bore, so as for said cylindrical neck, when covered by said J-slot sleeve, forms an annular flow space, fluid connecting said upper and lower stinger ports and thus said central connector and stinger bores.

The stinger portion may have a rotatable outer cylindrical body arranged on an inner cylindrical body, i.e. a cylindrical inner, static, stinger valve stem body, of said stinger portion and extending and covering at least to above said lower stinger port.

There may further be provided a sealing device as described above which is arranged in the lower stinger port, movably in a radial direction of the lower stinger port.

The outer cylindrical body may have a sleeve valve port arranged for being aligned with said lower stinger port when rotated into an open position, and the rotatable outer cylindrical body is connected to said lugs for being rotated RH or LH by said drill pipe string for opening or closing the valve.

Embodiments of the invention are defined in the dependent claims.

Brief Figure Captions

The invention is illustrated in the attached drawings, wherein

Fig. 1 is an illustration view of an embodiment of the invention wherein a stinger (10) with a valve according to the invention is extending from the right of the drawing towards the left, and illustrated as arranged in a run-in conveyed position and prevented from collapsing by a spline sleeve (112) in an outlined section of a J-slot sleeve (21) of a J-slot running tool (20), a so-called J-slot connector, extending from the left side of the drawing. The spline sleeve (112) is for axial holding of lugs (12) in the J-slot bottom. There may be arranged run-in shear pins in addition to the spline sleeve. A novel feature of the stinger (10) readily visible in the drawing is the cylindrical neck (13) formed at the stinger portion (11) and its related upper and lower stinger ports (15, 17, 34). Up is to the left in the drawing, down into the well is to the right. A lower threaded connection (41) for the central stinger bore (32) to the central bore and the top of a below bridge plug is to the right. A central connector bore (30) for being connected to the bore of a drill pipe string is to the left in Fig.1.

Fig. 2 is an axial section of the stinger (10) and an axial section of the associated J-slot running tool (20). An important feature is the rotatable, outer cylindrical body (18o) (o for "outer") which is provided with a sleeve valve port (34) for opening by alignment with the lower stinger port (17) to the central stinger bore (32) of the stinger (10). It closes by rotational non-alignment of the sleeve valve port (34) with the lower stinger port (17). The outer cylindrical (18o) is connected to the lugs (12) so as for being rotated right-hand (RH) or left-hand (LH) by the J-slots of the J-slot running tool (20).

When the outer cylindrical body (18o) has been rotated to close the lower stinger port (17), the operator may put weight on the drill pipe string to collapse the stinger (10) head (133) past the spline sleeve (112) into the bottom of the J-slot running tool (20), rotate the lugs (12) out of the pocket of the J-slot (22), pull up and disconnect. The stinger (10) on top of the bridge plug is now closed. Reconnection and opening are done in the opposite order. When disconnected, the cylindrical neck (13) of the stinger portion no longer forms any annular flow space (31) due to the absence of the J-slot running tool (20), and the sleeve valve port (34) is bare. A significant advantage of the invention is that the seal ring (50) is covered by the outer cylindrical body (18o) when closed, so it is protected from any debris which always will precipitate to some degree onto the stinger.

Fig. 3 is an image of the lower stinger port (17) in the inner cylindrical body (18i), i.e. the inner, static stinger valve stem body, seen from a near-tangential transverse view angle relative to the port. A seal ring (50) held by a seal retainer ring (52) such as a rigid, flexible PEEK, is shown. The seal groove (51) is milled into the outer surface of the inner cylindrical body (18i) in a way as to ensure a wrapped cross-section profile in the cylindrical surface: a flat, circular retainer ring (52) is snapped into the wrapped groove (51) to hold the seal ring (50). The milling of the seal groove (51) is made using a multi-axial milling tool and not a mono-axial one, in order to produce the seal groove (51) with the same cross section relative to the radial line on the surface of the lower stinger port (17). The seal ring (50) seals against the inner surface of the outer outer cylindrical body (18o), please see Fig.6 and Fig.5. One significant advantage of the present invention is the relatively small diameter of the seal ring (50), thus its small exposed area subject to friction from the surrounding outer cylindrical body (18o), thus reducing friction and wear during opening and closing.

Fig. 4 is an oblique near-axial image of the same lower stinger port (17). Also here is shown how the ring groove (51) is milled as if it wraps into the cylindrical surface about the lower stinger port (17). The seal retainer ring (52) is more rigid than the seal ring (50) but is sufficiently flexible to be snapped into the milled, undercut seal groove (51). The lower stinger port (17) itself may be a simple cylindrical lateral bore drilled into the inner cylindrical body (18i).

Fig. 5 is an illustration of an axial section of the inner and outer cylindrical bodies (18i, 18o) in the vicinity of the lower stinger port (17). A longitudinal section of the lower stinger port (17) and the seal and seal retainer rings (50, 52) is shown.

Fig. 6 is a corresponding cross section of the inner and outer sleeve valve bodies (18i, 18o), the section made at the lower stinger port (17) and the sleeve valve port (34). A circular cross section of the lower stinger port (17) and the wrapped seal and seal retainer rings (50, 52) is shown. Projection of the lugs (12) (not in the same cross section) are shown on the outer cylindrical body (18o) with the sleeve valve port (34) rotated 90 degrees out of alignment with the lower stinger port (17).

Fig. 7 is an enlarged portion of the section of Fig.5, which shows the outer groove lip (51o) into which the retainer ring (52) is snapped, and a corresponding inner groove lip (51i) for holding the seal ring (50) assisted by the seal ring (50) inward facing lip. Opening the valve half way then closing again under high pressure poses a risk of clipping the retainer ring, but such clipping is prevented by fully opening before fully closing.

In Fig.8-11 there is shown another sealing arrangement 200 which is arranged in a port of an inner cylinder of a downhole tool.

Embodiments of the invention

The invention is a petroleum well toolstring valve comprising a drill pipe stringconveyed J-slot running tool (20) for a stinger (10) on a retrievable bridge plug, which may be called a tool.

The J-slot running tool (20) has the following main components:

- a central connector bore (30) which is fluid communicating upwardly with said drill pipe string, and

- a J-slot sleeve (21) with J-slots (22) for running, disconnecting and retrieving said stinger (10) into a well. The J-slots (22) are open downwardly in the longer one of their branches, and closed in the J-slot pocket.

The stinger (10) has the following main components:

- a cylindrical stinger portion (11) with a central stinger bore (32), J-slot connecting lugs (12), and a lower connection (41) , usually threaded, for attachment of a tool, such as a retrievable bridge plug, to the lower connection (41), where the tool is arranged for working in selectable fluid communication with said central connector bore (30) and thus said drill pipe string.

One of the main purposes of having fluid communication through the bridge plug via the stinger (10) and the J-slot sleeve (21) and further through the drill pipe string, is to enable ventilating and balancing out gas and fluid pressure from below the bridge plug in order to enable releasing the slips and packer of the plug without any pressure or gas gradient across the plug. A further purpose of enabling fluid communication via the drill pipe string is to allow testing pressure integrity of the packer; whether a set packer of the plug actually seals against pressure from below and pressure from above, before disconnecting and pulling off the drill pipe string.

In the background art, the central bore of the drill pipe string, the central connector bore (30), and the central stinger bore (32) are in axial fluid communication for controlling the below tool with fluid communication such as pressure and flow rate, directly from the drilling rig at the surface. Also, usually, in order to open or close central bore there is arranged a ball valve section in the bridge plug itself, which ball valve is a rather delicate, multi-component tool part which is costly, vulnerable, and which requires much maintenance between runs. The present invention valve replaces such a ball valve.

In the present invention the central stinger bore (32), in the closed state of the valve, isolated from the central connector bore (30) by an internal plug (33). The stinger portion (11) has a cylindrical neck (13) spanning said internal plug (33) in the axial direction, and is provided with

- an upper radial port (15) into said central connector bore (30) (and above the internal plug (33)) which communicates upwardly, and

- a lower stinger port (17) into said central stinger bore (32) (below the internal plug (33)) which communicates downwardly.

Then the cylindrical neck (13), when covered by the J-slot sleeve (21), forms an annular flow space (31) connecting said upper and lower radial ports (15, 17) and thus said central connector and stinger bores (30, 32). This allows ordinary J-slot connectors to be used with little or no modification. The opening and closing of the fluid communication between said central connector bore (30) and central stinger bore (32) takes place by opening and closing the lower stinger port (17), as follows:

The stinger portion (11) has a flush outer cylindrical body (18o) arranged on an inner cylindrical body (18i), i.e. a cylindrical inner, static, stinger valve stem body, of said stinger portion (11) and extending at least to above said lower stinger port (17), and the outer cylindrical body (18o) has a sleeve valve port (34) arranged for being aligned with said lower stinger port (17) when rotated into an open position. Further, the outer cylindrical body (18o) is connected to the lugs (12) and rotated together with those, for being rotated RH or LH by the J-slot sleeve (21) which is a running tool conveyed on the drill pipe string, in order to open or close the lower stinger port (17).

The rotation direction for closing the port preferably is the same as the rotation direction for disconnecting the J-slot tool, and vice versa.

There are significant advantages of this simple valve arrangement. A ball valve, which is a delicate mechanism and which requires a solid, through bore ball valve element wherein the through bore opening is less than a quarter of the circumference of the ball, and which requires two vulnerable full bore seals arranged above and below the ball, and a link arm mechanism for opening or closing linked to a rotating sleeve, an axially translating sleeve, or both. The ball valve mechanism is costly to build, and costly to maintain, and the maintenance may be necessary to conduct for each time the ball valve has been run. The ball valve mechanism must be disassembled for inspecting the valve seals. Contrary to the ball valve mechanism, the valve of the present invention may be operated by rotating the lugs using the running tool rotated by the drill pipe string. The mechanism closes by a quarter turn to left and opens by the opposite turn, to the right, or vice versa, depending on the preference of the mechanical designer. Sealing the lower stinger port (17) requires a significantly smaller seal than a full bore seal, thus the seal friction in the valve element of the present invention is less than the seal friction in the ball valve mechanism of the prior art, which results in a smaller required rotational moment and less wear for operating the present invention

A further advantage, when requiring less torque due to less friction for opening or closing, we have reduced the risk of breaking / unscrewing a threaded connection in the drill pipe string upon opening or closing, the one of those which requires left hand rotation (LH). We also save rig time because we need to establish less torque. The invention thus results in increased operation safety and reduced rig time.

In an embodiment of the invention, In the valve, the outer cylindrical body (18o) and the inner cylindrical body (18i) has rotation delimiter shoulders (14o, 14i), respectively, arranged for limiting mutual LH or RH rotation relative to said stinger portion (11). It is practical to limit the mutual rotation to 90 degrees, and at least to less than about 180 degrees, due to required mechanical strength of the shoulders (14o, 14i). In an embodiment of the invention the inner cylindrical body (18i) and the outer cylindrical body (18o) is provided with one lower stinger and sleeve valve port (17, 34), and may in an alternative be provided with an oppositely arranged pair of lower stinger and sleeve valve ports (17, 34). The person skilled in the art, given the present description and drawings, would of course be capable of devising further ports, but for the present invention, we consider one lower stinger and sleeve valve port (17, 34) as sufficient.

In an embodiment of the invention there is at least one sealing o-ring (110) arranged on said stinger portion (11) between said lugs (12) and said cylindrical neck (13). The sealing O-ring (110) on the stinger portion (11) may be of rectangular crosssection or of circular cross-section. The sealing O-ring (110) will sit at the exposed surface of the stinger portion (11) and should be rather rugged considering its use which includes stabbing under usually particle polluted conditions.

In an embodiment of the invention, please see Figs 3 and 4, and also Figs.5 and 6, with some more detail in Fig.7, illustrates a seal ring (50) arranged about said lower stinger port (17). The seal ring (50) is arranged in a ring-shaped groove (51) milled into in said inner cylindrical body (18i). The small diameter of the seal ring (50) provides a small exposed seal area. In an embodiment of the invention the seal ring (50) is held in the ring-shaped groove (51) by a ring-shaped seal retainer (52) which snaps into the seal groove (51) by means of having larger diameter than an outer lip (51o) of the milled groove.

The workings of the invention

Archer's valve is operated by a J-slot connector with a J-slot (22) inside the cylindrical sleeve for receiving and connecting to the stinger with the lugs running into the J-slot (22). The stinger head (133) of the stinger (10) abuts in a spline sleeve (112) to hold the lugs (lower down on the stinger (10) in place in the J-slot pocket when running in. Rotation is used to open and close the valve. Weight down to compress the stinger into the J-slot connector tool, and rotate to release.

The opening and closing of the valve is done by rotating the drill pipe string, thus rotating the lugs (12) with the stinger portion (11)'s outer cylindrical body (18o), for aligning the sleeve valve port (34) of rotating sleeve valve body (18), with the lower stinger port (17) of the cylindrical stem with the central stinger bore (32) of the stinger, which communicates with the plug below.

The central stinger bore (32) is blocked by an internal plug (33). When the lower stinger and sleeve valve port (17, 34) is open, the central stinger bore (32) of the stinger communicates via an internal annular flow space (31) with another port (15) to the central connector bore (30) of the J-slot connector, further communicating with the drill pipe string.

The sealing O-ring (110) on the stinger portion (11) may be of rectangular crosssection or of circular cross-section. The sealing O-ring (110) will sit at the exposed surface of the stinger portion (11) and should be rather rugged considering its use which includes stabbing under polluted conditions.

Below, a brief explanation of the sealing device 200 according to the present invention is described with reference to Fig.8-11.

Pressure from the inside of inner piston 204 will activate inner piston 204 and apply a force to the metal seal areas 223, 224, i.e. the inner surface part 223 and an outer surface part 224 of the outer surface of the outer piston 219. The fluid pressure will push on the inner piston 204 and the outer piston 219 with the inner surface part 223 and the outer surface part 224.

Increasing pressure will give higher force to the metal seal 223 and 224 and better the sealing. The metal seal area 223, i.e. the inner surface part 223, will hold fluid pressure and protect the seal from damage. The seal 232 will hold gas pressure and works as an extra barrier against the pressure (i.e. dual seal).

Pressure from the outside of inner piston 204 will activate outer piston 219 by applying pressure to the spring recess 211 of the outer piston through the gap between the outer piston 219 and port in which the sealing device is arranged, and/or through fluid channels. This pressurized fluid will apply a force to the metal seal area 223 and 224, i.e pushing the inner surface parts 223 and 224 against the outer cylindrical body 18o which is coaxial with the inner cylindrical body 18i.

Increasing pressure will give higher force to the metal seals 223 and 224 and better the sealing. The metal seal area 224 will hold fluid pressure and protect the seal from damage. The seal 232 will hold gas pressure and works as an extra barrier the pressure. (Dual seal).

The metal seal areas 223 and 224 will hold pressure and protect the gas seal during opening and closing at full pressure.

This design of the sealing device 200 for the port enables pressures from both sides (i.e. inside and outside of the port) to activate the metal seal 223, 224.

Reference numbers for the sealing device 200 shown in figures 8-11:

Claims

PATENT CLAIMS

1. A sealing device (200) for a down-hole tool comprising an inner cylindrical body (18i) and an outer cylindrical body (18o) which are provided with respective axial bores and are coaxially arranged, and where the inner cylindrical body (18i) is provided with a port extending in a radial direction of the inner cylindrical body, in which port the sealing device (200) is adapted to be arranged movably in said radial direction, the sealing device (200) having a longitudinal axis which extends in the same direction as the radial direction of said port when the sealing device is arranged in the port, the sealing device (200) comprising:

- an inner piston (204) which is adapted to be arranged in said port movable relative to the inner cylindrical body (18i) of the down-hole tool, the inner piston (204) comprising:

a seat portion (207) which is adapted to abut a seat in said port of the cylindrical body of the down-hole tool, a neck portion (208) extending outwards from the seat portion (207) in said longitudinal direction,

an inner piston fluid conduit (205) extending through the seat portion (207) and the neck portion (208) in said longitudinal direction,

- a first sealing element (230) extending circumferentially around the inner piston (204) and being adapted to seal against said port when the sealing device (200) is arranged in the port such that radial fluid flow past the inner piston (204) between the inner piston (204) and the port of the inner cylindrical body (18i) is prevented,

characterized in that the sealing device (200) further comprises:

- an outer piston (219) which is adapted to be arranged in said port movable relative to the inner cylindrical body (18i) of the down-hole tool, the outer piston (219) being movable relative to the inner piston (204) in said longitudinal direction and guided by the neck portion (208) of the inner piston (204), the outer piston (219) comprising:

an outer piston fluid conduit (220) extending through the outer piston (219) in said longitudinal direction,

an outer surface (222) which faces radially outwards when the sealing device (200) is arranged in said port and extends circumferentially around the outer piston fluid conduit (220), the outer surface (222) being adapted to form a seal against the outer cylindrical body (18o) when the sealing device (200) is arranged in said port,

- a spring device (227) which is arranged between the inner piston (204) and the outer piston (219) so that forces are exerted in opposite longitudinal directions on the inner piston (204) and the outer piston (219) respectively, the spring device (227) exerting a force radially inwards on the inner piston (204) and a force radially outwards on the outer piston (219) when the sealing device (200) is arranged in said port,

- a second sealing element (231) arranged between the inner piston (204) and the outer piston (219) preventing radial fluid flow past the neck portion (208) of the inner piston (204) between the outer piston (219) and the neck portion (208),

- a third sealing element (232) which is arranged in the outer surface (222) of the outer piston (219) and extending circumferentially around the outer piston fluid conduit (220), the third sealing element (232) being adapted to form a further seal against the outer cylindrical body (18o) when the sealing device (200) is arranged in said port.

2. The sealing device according to claim 1,

wherein the first sealing element (230) extends circumferentially around the neck portion (208) of the inner piston (204).

3. The sealing device according to claim 1 or 2,

wherein the third sealing element (232) divides the outer surface (222) into an inner surface part (223) and an outer surface part (224).

4. The sealing device according to one of the claims 1-3,

wherein the outer piston (219) is made of a metallic material.

5. The sealing device according to one of the claims 1-4,

wherein an outer side face of the outer piston (219) facing the port when the sealing device (200) is arranged in the port, is provided with a plurality of canals extending along the entire outer side face or at least substantially the entire outer side face such that fluid can flow from a space between the inner cylindrical body (18i) and outer cylindrical body (18o) and into a spring recess (211).

6. The sealing device according to one of the claims 1-5,

wherein the inner piston (204) is provided with a spring recess (211) which faces the outer piston (219), where the spring device (227) is arranged in the spring recess (211).

7. The sealing device according to claim 6,

wherein the spring recess (211) is provided in the seat portion (207) of the inner piston (204).

8. The sealing device according to one of the claims 6-7,

wherein the spring device (227) is a wave spring.

9. The sealing device according to one of the claims 1-8,

wherein the inner piston fluid conduit (205) and the outer piston fluid conduit (220) form a fluid conduit which allows a fluid to flow through the sealing device (200) in the longitudinal direction of the sealing device (200).

10. The sealing device according to one of the claims 1-9,

wherein the first sealing element (230), the second sealing element (231) and the third sealing element (232) are made of an elastomer.

11. The sealing device according to any one of the claims 1-10,

wherein the sealing device (200) is adapted to be arranged in a top stinger (10) comprising an inner cylindrical body (18i) with a lower stinger port (17) and an outer cylindrical body (18o) with a sleeve valve port (34), the inner cylindrical body (18i) and the outer cylindrical body (18o) being coaxial and rotatable relative to each other, the sealing device (200) being adapted to be arranged in the lower stinger port (17), movably in the radial direction in the lower stinger port (17).

12. A downhole tool comprising an inner cylindrical body (18i) and an outer cylindrical body (18o) which are provided with respective axial bores and are coaxially arranged, and where the inner cylindrical body (18i) is provided with a port extending in a radial direction of the inner cylindrical body (18i),

characterized in that a sealing device (200) according to any of the claims 1-11 is arranged in the port, movably in the radial direction.

13. The downhole tool according to claim 11 or 12,

wherein the port of the inner cylindrical body (18i) comprises a seat against which the sealing device (200) is abutting.

14. The downhole tool according to one of the claims 11-13,

wherein the inner surface part (223) of the outer surface (222) and an outer surface part (224) of the outer surface (222) both forms a seal against fluid flow across the outer surface (222).

15. A petroleum well toolstring valve comprising a drill pipe string conveyed J-slot running tool (20) for a top stinger (10) on a retrievable bridge plug, both having a central connector and central connector and stinger bores (30, 32),

said J-slot running tool (20) having

- a J-slot sleeve (21) with J-slots (22) for disconnectably receiving said stinger (10) with lugs (12) of said top stinger (10);

- said top stinger (10) having

- a cylindrical stinger portion (11) with

- J-slot connecting lugs (12), and

- an internal plug (33) is arranged between said connector and central connector and stinger bores (30, 32);

- a cylindrical neck (13) is formed on said stinger portion (11), spanning said internal plug (33) in the axial direction, with

- an upper stinger port (15) into said central connector bore (30), and

- a lower stinger port (17) into said central stinger bore (32),

so as for said cylindrical neck (13), when covered by said J-slot sleeve (21), forms an annular flow space (31), fluid connecting said upper and lower stinger ports (15, 17) and thus said central connector and stinger bores (30, 32),

- said stinger portion (11) having

- a rotatable outer cylindrical body (18o) arranged on a static, inner cylindrical body (18i) of said stinger portion (11) and extending and covering at least to above said lower stinger port (17),

- said outer cylindrical body (18o) having a sleeve valve port (34) arranged for being aligned with said lower stinger port (17) when rotated into an open position,

characterized in that a sealing device (200) according to any of the claims 1-11 is arranged in the lower stinger port (17), movably in a radial direction of the lower stinger port (17).

16. The petroleum well toolstring valve according to claim 15,

wherein said stinger portion (11) having said outer cylindrical body (18o) connected to said lugs (12) for being rotated RH or LH by said drill pipe string for opening or closing said valve

17. The petroleum well toolstring valve according to claim 15 or 16,

wherein said outer cylindrical body (18o) and said static stinger valve stem body (18i) having rotation delimiter shoulders (14o, 14i), respectively, arranged for limiting mutual LH or RH rotation relative to said stinger portion (11).

18. The petroleum well toolstring valve according to one of the claims 15-17, comprising at least one sealing o-ring (110) arranged on said stinger portion (11) between said lugs (12) and said cylindrical neck (13).

19. The petroleum well toolstring valve according to one of the claims 15-18, wherein the lower stinger port (17) comprises a seat against which the sealing device (200) is abutting.

20. The petroleum well toolstring valve according to one of the claims 15-19, wherein the inner surface part (223) of the outer surface (222) and an outer surface part (224) of the outer surface (222) both forms a seal against fluid flow across the outer surface (222).